I bought a pair of these tubes to go in the front tires of my 1946 International Harvester tractor in the spring of 2009 and they have worked flawlessly for the past year and a half. I regularly drive the tractor through the woods skidding logs so it is exposed to possible punctures and has yet to burst.
When this set of tires wears out, I'll put an identical set of tubes in the tires if this pair is no longer usable.
My girlfriend gave me one of these for my 1946 International I-4 for my birthday along with a rain flap and the clamp. So far it has worked great, much better than the steel straight pipe that I used to have on there. The outlet was a little tall for using in the woods, so I trimmed it in half for better clearance. The metal isn't very thick, maybe 1/16", but it has proven to be very sturdy when getting hit with low limbs.